A U.S. security institute has published satellite images which it said increased concerns that Iran was trying to "destroy evidence" of suspected past research relevant for developing a nuclear weapons capability, a charge Tehran dismisses.

The Institute for Science and International Security (ISIS) posted them on its website hours after diplomats said the U.N. atomic watchdog showed what appeared to be similar imagery at a closed-door briefing in Vienna.

Western envoys who attended Wednesday's briefing earlier told Reuters that two small side buildings at the Parchin military facility had been removed, and ISIS said its pictures from May 25 showed that they "have been completely razed".

The disclosure followed inconclusive talks between Iran and six world powers in Baghdad last week to address concerns about the nature of its nuclear activities, which Iran says are aimed at generating electricity.

The U.N. International Atomic Energy Agency (IAEA) has repeatedly asked Iran for access to Parchin as part of a long-stalled probe into suspicions that Tehran may be seeking the ability to assemble nuclear bombs, should it decide to do so.

The Islamic state has so far refused to let inspectors visit the facility - which it describes as a conventional military complex - saying there must first be a broader framework agreement on how to address the IAEA's questions.

The new satellite images will add to Western suspicions that Iran is "sanitizing" the site of any incriminating evidence before allowing the IAEA to go there.

Iran's IAEA envoy, Ali Asghar Soltanieh, dismissed such accusations by Western officials, telling reporters after the briefing at IAEA headquarters that "this kind of noise and allegations are baseless".

ISIS, which tracks Iran's nuclear programme closely, said there were visible tracks in the images "made by heavy machinery used in the demolition process", adding that the two buildings had been intact in early April.

No Parchin Access?

"Heavy machinery tracks and extensive evidence of earth displacement is also visible throughout the interior as well as the exterior of the site's perimeter," the think-tank said.

The Parchin complex is at the centre of Western allegations that Iran has been conducting research and experiments that could serve a nuclear weapons development programme. The Islamic Republic has repeatedly denied any such ambition.

Last week, the IAEA said in a report issued to member states that satellite images showed "extensive activities" at the facility southeast of Tehran.

Western diplomats said this was an allusion to suspected cleaning at Parchin. They have earlier cited other images showing recent activity at the site, including a stream of water, as suggesting Iran is trying to remove evidence.

Iran, which denies Western accusations it is seeking to develop nuclear weapons capability, has dismissed charges aired about Parchin as "childish" and "ridiculous".

"The newest image raises concerns that Iran is attempting to raze the site prior to allowing an IAEA visit. The razing of the two buildings may also indicate that Iran has no intention to allow inspectors access soon," ISIS said.

An IAEA report last November said Iran had built a large containment vessel in 2000 at Parchin in which to conduct tests that the U.N. agency said were "strong indicators of possible (nuclear) weapon development."

It said a building was constructed around a large cylindrical object, a vessel designed to contain the detonation of up to 70 kg of high explosives. Diplomatic sources say the suspected tests likely took place about a decade ago.

Last week, a senior Iranian official was quoted as saying the IAEA had not yet given good enough reasons to visit Parchin.

Comment: Images and words about tracks in dirt made by heavy machinery is offered as proof. No mention of earlier International Atomic Energy Agency Reports where the IAEA clearly said Iran is not a nuclear threat and has no nuclear ambitions in any military capacity.

Things are starting to take a repeat roll of Iraq, Afghanistan and Libya. The obvious target: Iran.

By the way, construction in and around nuclear sites is not uncommon. In simple terms; a construction company who did work inside the facility leveled the lunchroom they built for their workers, since work at the site was complete. Leave it to the West to always conclude (for us) the worst, while bastardizing free decent people, whose resources the 1% intend on plundering.